1. Field of the Invention
The present invention relates generally to ignition systems for internal combustion engines and, more particularly, to systems that increase the spark current to the engine's spark plugs.
2. Background of the Prior Art
Ignition systems have long been used to provide spark current to the spark plugs of an internal combustion engine. Before electronic ignition systems, spark plugs were “fired” by energizing and de-energizing a primary winding in a coil via mechanical contacts that were in parallel with a capacitor (often called a condenser). The primary winding caused a current to flow from a secondary winding to a preselected spark plug. The contacts opened and closed to remove power from a battery that ultimately energized the primary winding. To avoid rapid deterioration of the contacts, the capacitor was added to “absorb” an arc that would otherwise occur across the contacts when they started to open. When the contacts closed, the capacitor would discharge then the cycle would repeat. With the advent of electronic ignition and solid state switches, arcing contacts and arc absorbing capacitors were deleted from ignition systems.
Irrespective of the ignition system being electronic or of an earlier vintage, the spark size, duration and firing time influence the combustion process inside the cylinders of the engine which correspondingly affects the power generated. A typical prior art electronic ignition system is depicted in FIG. 1 of the drawings. The system includes a battery 22 that provides an electrical current to a primary winding 16 when a transistor or solid state switch 14 is closed. When the switch 14 is opened, the current goes to zero and the magnetic field generated by the current collapses thereby inducing a high voltage in a secondary winding 18 resulting in a secondary current flowing through the winding 18 which generates a spark across the electrodes of a spark plug 20.
Power output from the engine increases when the magnitude of the secondary current is increased or when the rise time of the secondary current is decreased. To achieve either these objective, expensive components are added to the electronic ignition system and/or existing components are replaced. Prior art techniques for increasing power output have not considered storing energy from the primary winding 16 as the primary current goes to zero when the switch 14 is opened, then directing the stored energy as a reverse current flow back through the primary winding 16. The reverse current flow increases the peak-to-peak current through the primary winding, and correspondingly increases the current through the secondary winding which ultimately provides the spark current to the spark plugs.
A need exists in the art for a system and/or method that economically and quickly increases the current through the secondary winding and spark plug of an electronic ignition system for either newly manufactured or in use prior art designed electronic ignition systems.